Arrhythmias are due to irregular contractions and disorganized electrical signals within the heart and are a leading cause of death in the United States (US). Ventricular tachycardia and ventricular fibrillation are the most-serious arrhythmias and are associated with 300k annual US deaths. In comparison, atrial fibrillation (AF) impacts 6M Americans, making it the most common arrhythmia. With nearly 750k annual US hospitalizations and 130k annual US deaths, AF is associated with the highest medical costs, which are projected to exceed $50B by 2035. First-line AF therapies rely on pharmaceuticals to prevent blood clots and to restore proper rhythm. When these approaches fail, catheter ablation is an option. For this procedure, electrical currents (or coolants) are directed to the catheter?s tip to ablate those tissues disrupting normal electrical signals. Catheter ablation is an effective and increasingly-used therapy, with more than 500M procedures performed between 2000 and 2013. However, standard methods are complex and expose electrophysiologists to x-rays. Because manually-deflectable catheters rely on complex tension-wire designs that are operated from a meter away, errors accumulate in the transmission of forces and torques. As a result, precise catheter navigation and heart- wall contact are challenging, which can result in injury and AF recurrence (observed in ~50% of those treated). Robotic platforms attempt to address manual ablation catheter deficiencies. Standard robotic systems manipulate traditional manual catheters and place the electrophysiologist outside the x-ray field. However, the technology?s learning curve is high, catheter tip control is unimproved, and systems are expensive. Magnet- based robotic systems improve upon standard robotic systems by using magnetic fields to apply forces and torques directly to magnet-tipped catheters, which simplifies the catheters. The result is a technology that provides improved navigation and better heart-wall contact. However, magnet-based systems are impractically large, very expensive, hard to install, and difficult to use, in addition to requiring a new c-arm and magnetic shielding for the room. For these reasons, broad adoption of all AF robotic solutions has been slow. As opposed to expending energy in fighting the catheter?s restoring force, the proposed technology redesigns the catheter so that better catheter navigation and heart-wall contact are accomplished using a system whose magnetic field and mass are 6X and 40X smaller, respectively, than previously possible. The result is an affordable technology that 1) provides better catheter-tip control and heart-wall contact, 2) offers an open catheter lumen for electrical leads and irrigation, and 3) does not require custom c-arms and room construction. The team reflects commercially-successful magnetics, robotics, and electrophysiology experts. The Phase I effort focuses on proof of concept of the platform. The aims include 1) building the prototype magnet system, 2) building catheters and advancer, and 3) evaluating the system?s performance in beating heart phantoms. An FDA pre-submission meeting will be conducted in advance of the Phase II proposal.